For 1981 to 1984 300SD Diesel engine.
Wire harness as shown. Note this one is for the 300SD as it has the long wire going down to the oil pressure sending unit.
W126 300SD Glow Plug System Wiring Harness - USED
$65.00
SKU:
USED-300SDGLOWWIRES 
Product Details
Related Products:
$58.00
Late OM617 5 Cylinder Glow Plug Relay - USED
Last one. Fits 1981 To 1985 300D, 300CD, 300TD and 300SD
Excellent tested used glow relay. No cover included but can be purchased separately below
$65.00
617 300SD 300D 300CD TD Bosch Pencil Glow Plugs - Set of 5 with instructions
Fits 1980 to 85 300D 300CD 300TD and 1978 to 1985 300SD
Application: Fits all 116 and 126 Chassis 5 cylinder diesel engines 300SD from 1978 to 1985 and all 123 Chassis 300D, 300CD and 300TD from 1980 to 1985 with pencil glow plugs. Excellent quality. Five Bosch Duraterm pencil plugs with installation instructions.